• Mycobiology
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• v.38 no.4
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• pp.238-248
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• 2010

This review provides background information on the importance of bioremediation approaches. It describes the roles of fungi, specifically white rot fungi, and their extracellular enzymes, laccases, ligninases, and peroxidises, in the degradation of xenobiotic compounds such as single and mixtures of pesticides. We discuss the importance of abiotic factors such as water potential, temperature, and pH stress when considering an environmental screening approach, and examples are provided of the differential effect of white rot fungi on the degradation of single and mixtures of pesticides using fungi such as Trametes versicolor and Phanerochaete chrysosporium. We also explore the formulation and delivery of fungal bioremedial inoculants to terrestrial ecosystems as well as the use of spent mushroom compost as an approach. Future areas for research and potential exploitation of new techniques are also considered.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.278-284
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• 2011

The CCR4-CAF1-NOT complex-mediated degradation of mRNA is a fundamental aspect of gene regulation in eukaryotes. We herein examined the role of AtCAF1 in the innate immune and wound responses of plants. Our results showed that overexpression of AtCAF1 significantly downregulated the transcript level of EFR but not FLS2 and BRI1, as well as abolished up-regulated expression pattern of EFR in response to wounding. Consistently, Agrobacteriummediated transient expression of GUS was highly enhanced in the transgenic plants overexpressing AtCAF. Furthermore, JA responsive genes were down-regulated by overexpression of AtCAF, causing the transgenic plants overexpressing AtCAF more susceptible to necrotrophic fungal pathogen, Botrytis cinerea. These results suggest that The CCR4-CAF1-NOT complex-mediated degradation of mRNA negatively regulates wounding-mediated disease resistance in Arabidopsis thaliana.

• Mycobiology
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• v.35 no.4
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• pp.196-204
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• 2007

The growth and bioconversion potential of selected strains growing on cassava waste substrate during solid state fermentation were assessed. Rhizopus stolonifer showed the highest and the fastest utilization of starch and cellulose in the cassava waste substrate. It showed 70% starch utilization and 81% cellulose utilization within eight days. The release of reducing sugars indicating the substrate saccharification or degradation potential of the organisms reached the highest value of 406.5 mg/g by R. stolonifer on cassava waste during the eighth day of fermentation. The protein content was gradually increased (89.4 mg/g) on the eighth day of fermentation in cassava waste by R. stolonifer. The cellulase and amylase activity is higher in R. stolonifer than A. niger and P. chrysosporium. The molecular mass of purified amylase and cellulase seemed to be 75 KDal, 85 KDal respectively.

• Journal of Microbiology and Biotechnology
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• v.19 no.6
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• pp.573-581
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• 2009

The complex enzyme pool secreted by the phytopathogenic fungus Fusarium graminearum in response to glucose or hop cell wall material as sole carbon sources was analyzed. The biochemical characterization of the enzymes present in the supernatant of fungal cultures in the glucose medium revealed only 5 different glycosyl hydrolase activities; by contrast, when analyzing cultures in the cell wall medium, 17 different activities were detected. This dramatic increase reflects the adaptation of the fungus by the synthesis of enzymes targeting all layers of the cell wall. When the enzymes secreted in the presence of plant cell wall were used to hydrolyze pretreated crude plant material, high levels of monosaccharides were measured with yields approaching 50% of total sugars released by an acid hydrolysis process. This report is the first biochemical characterization of numerous cellulases, hemicellulases, and pectinases secreted by F. graminearum and demonstrates the usefulness of the described protein cocktail for efficient enzymatic degradation of plant cell wall.

• Journal of the Korean Wood Science and Technology
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• v.20 no.3
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• pp.55-60
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• 1992

Japanese red pine (Pinus densiflora S. et. Z.) decayed by brown-rot fungi Tyromyces palustris and Gloeophyllum trabeum were subjected to X-ray diffraction analysis and infrared spectral examinations. Pine woods decayed by T. palustris showed the increase of relative crystallinity in the initial stage of degradation. When the weight loss was above 30%, then the crystallinity went down slowly. In contrast, the wood samples degraded by G. trabeum showed the decrease of crystallinity from the beginning stage of decay. The changes of crystallinity in brown-rotted woods suggested that the degradation rate of crystalline cellulose was varied with the brown rot fungal species. X-ray diffraction analyses also indicated that crystalline cellulose was much more slowly broken down than the amorphous one. The most notable difference in the IR spectra of the brown-rotted wood samples was that the adsorption band centered at 1,730$cm^{-1}$ was significantly diminished in the decayed wood. indicating the degradation of hemicellulose by brown-rot fungi. However, no marked changes of intensities at 1,000, 1,060 and 1,040$cm^{-1}$ were observed in the brown rotted wood samples, suggesting that crystal line cellulose was resistant against the attack by brown rot fungi.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.1-14
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• 1999

As the biodegradation of wood constituents has been understood as a multi-basidiomycetes and enzymatic processes, this review will focus on the roles of low molecular compounds and radicals working in harmony with fungal enzymes. Wood rotting basidiomycete fungi penetrate wood, and lead to more easily metabolize carbohydrates of the wood complex. The white-rot fungi, having versatile enzymes, are able to attack directly the "lignin barrier". They also use a multi-enzyme system including so-called "feedback" type enzymes allowing for simultaneous degradation of lignin and carbohydrates. The multi-enzymes including laccase support the proposed route by explaining how the high molecular weight enzymes can function in the wood complex. These enzymes may function separately or cooperate each other. In addition, veratryl alcohol oxidase, cellobiose dehydrogenase, arylalcohol dehydrogenase, and particularly low molecular mediators and radicals have an important role in wood biodegradation. However, the possibility of other mechanism as well as other enzymes, as operating as feedback systems in the process of wood degradation, could not be excluded.

• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.168-181
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• 2017

Whole cell of Phanerochaete chrysosporium with reducing agent was applied to verify the degradation mechanism of aromatic compounds derived from lignin precisely. Unlike the free-reducing agent experiment, various degraded products of aromatic compounds were detected under the fungal treatment. Our results suggested that demethoxylation, $C_{\alpha}$ oxidation and ring cleavage of aromatic compounds occurred under the catabolic system of P. chrysosporium. After that, degraded products stimulated the primary metabolism of fungus, so succinic acid was ultimately main degradation product of lignin derived-aromatic compounds. Especially, hydroquinone was detected as final intermediate in the degradation of aromatics and production of succinic acid. In conclusions, P. chrysosporium has an unique catabolic metabolism related to the production of succinic acid from lignin derived-aromatic compounds, which was meaningful in terms of lignin valorization.

• Journal of Life Science
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• v.30 no.12
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• pp.1128-1139
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• 2020

Over recent years, it has become evident that food and agricultural products are easily contaminated by fungi of Aspergillus, Fusarium, and Penicillium due to rapid climate change, which is not only a global food quality concern but also a serious health concern. Owing to consumers' interest in health, resistance to preservatives such as propionic acid and sorbic acid (which have been used in the past) is increasing, so it is necessary to develop a substitute from natural materials. In this review, the role of lactic acid bacteria as a biological method for controlling the growth and toxin production of fungi was examined. According to recent studies, lactic acid bacteria effectively inhibit the growth of fungi through various metabolites such as organic acids with low molecular weight, reuterin, proteinaceous compounds, hydroxy fatty acids, and phenol compounds. Lactic acid bacteria effectively reduced mycotoxin production by fungi via adsorption of mycotoxin with lactic acid bacteria cell surface components, degradation of fungal mycotoxin, and inhibition of mycotoxin production. Lactic acid bacteria could be regarded as a potential anti-fungal and anti-mycotoxigenic material in the prevention of fungal contamination of food and agricultural products because lactic acid bacteria produce various kinds of potent metabolic compounds with anti-fungal activities.

• Korean Journal of Microbiology
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• v.53 no.3
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• pp.216-218
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• 2017

We here provide the complete genome sequence of Bacillus thuringiensis C25, the strain showing antagonistic effects on fungal phytopathogens. The genome comprised of 5,308,062 bp with 35.32% G+C content of a circular chromosome and a plasmid containing 308,946 bp with 32.23% G+C content. The chromosome and plasmid genome included 5,683 protein coding DNA sequences, 107 tRNA and 42 rRNA genes.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.329-335
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• 1992

Degradation of rice straw was observed to be higher (p<0.01) in the buffaloes than in cattle. At 48 h, the dry matter (DM) loss of straw for buffaloes was 53.6 0.8% and that for cattle was 48.7 2.6%. Palm press fibre (PPF) was poorly degraded in the rumen of both animal species. A loss of about 21% DM was observed in both cattle and buffaloes after 48 h of incubation in the rumen. The pattern of bacterial and fungal colonization of straw and PPF seemed to be similar in both cattle and buffaloes. Microbial colonization was restricted by plant structures like the silica crystals in both straw and PPF. The predominant bacteria colonizing both straw and PPF fragments were the rods. Eroded zones and digestion pits were pronounced in straw fragments after 1 h of incubation. The PPF fragments appeared undegraded even after 6 h of incubation. Fungal colonization of straw was rapid and extensive in both cattle and buffaloes. The sporangia observed in straw were mainly spherical or oval in shape, but fusiform sporangia with acuminate tip were predominantly seen in PPF fragments.